AIMS: To describe the rationale and design of the Which Heart failure Intervention is most Cost-effective & consumer friendly in reducing Hospital care (WHICH?) trial. METHODS: WHICH? is a pragmatic, multicentre, randomized controlled trial that seeks to determine if multidisciplinary management of chronic heart failure (CHF) patients post-acute hospitalization delivered in a patient's own home is superior to care delivered via a specialist CHF outpatient clinic. The composite primary endpoint is all-cause, unplanned recurrent hospitalization or death during 12-18 months of follow-up. Of 688 eligible patients, 280 patients (73% male and 66% principal diagnosis of CHF) with a mean age of 71 ± 14 years have been randomized to home- (n = 143) or clinic-based (n = 137) post-discharge management. This will provide 80% power (two-sided alpha of 0.05) to detect a 15% absolute difference in both the primary end-point and rate of all-cause hospital stay. Preliminary data suggest that the two groups are well matched in nearly all baseline socio-economic and clinical parameters. The majority of patients have significant co-morbidity, including hypertension (63%), coronary artery disease (55%), and atrial fibrillation (53%) with an accordingly high Charlson Index of Comorbidity Score (6.1 ± 2.4). PERSPECTIVE: Despite its relatively small size, the WHICH? trial is well placed to examine the relative impact of two of the most commonly applied forms of face-to-face management designed to reduce recurrent hospitalization and prolong survival in CHF patients.